The present disclosure relates to an energy storage system and, more particularly, to an energy storage system which synchronizes a plurality of power controllers controlling loads.
With the development of industry, the power demand has increased. In addition, as a load gap between day and night and a power usage gap between seasons and holidays have gradually increased, the decline of a load factor is intensified.
Recently, for this reason, various load management techniques for reducing a peak load by using surplus electric power are developed, and a typical example of such techniques is a battery energy storage system.
The battery energy storage system stores surplus electric power at night or surplus electric power generated from wind power and solar light and supplies electric power to a load by discharging the stored electric power during a peak load or a system fault.
In this manner, it is possible to achieve the maximum load reduction and load leveling.
Recently, an emerging smart grid due to the emergence of various new and renewable energy sources may be used for such a battery energy storage system.
The energy storage system (or the battery power storage system) may include a plurality of loads which receive power from a system or supply power, a plurality of slave power controllers controlling the plurality of loads, and a master power controller controlling the plurality of slave power controllers.
Each slave power controller may transmit, to a load under control thereof, a control signal for controlling the load to be discharged or charged.
In a related art, when the slave power controllers transmit control signals, the slave power controllers and a master power controller controlling the same are not synchronized, so that each slave power controller may output the control signal at a different point in time, and accordingly, each load outputs power at a different point in time.